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🔗 Game Oriented Assembly Lisp

🔗 Video games

Game Oriented Assembly Lisp (GOAL) is a programming language, a dialect of the language Lisp, made for video games developed by Andy Gavin and the Jak and Daxter team at the company Naughty Dog.

It was written using Allegro Common Lisp and used in the development of the entire Jak and Daxter series of games.

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🔗 Black Hole Electron

🔗 Physics 🔗 Physics/relativity

In physics, there is a speculative hypothesis that, if there were a black hole with the same mass, charge and angular momentum as an electron, it would share other properties of the electron. Most notably, Brandon Carter showed in 1968 that the magnetic moment of such an object would match that of an electron. This is interesting because calculations ignoring special relativity and treating the electron as a small rotating sphere of charge give a magnetic moment roughly half the experimental value (see Gyromagnetic ratio).

However, Carter's calculations also show that a would-be black hole with these parameters would be "super-extremal". Thus, unlike a true black hole, this object would display a naked singularity, meaning a singularity in spacetime not hidden behind an event horizon. It would also give rise to closed timelike curves.

Standard quantum electrodynamics (QED), currently the most comprehensive theory of particles, treats the electron as a point particle. There is no evidence that the electron is a black hole (or naked singularity) or not. Furthermore, since the electron is quantum-mechanical in nature, any description purely in terms of general relativity is paradoxical until a better model based on understanding of quantum nature of blackholes and gravitational behaviour of quantum particles is developed by research. Hence, the idea of a black hole electron remains strictly hypothetical.

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🔗 Black Arrow

🔗 Spaceflight 🔗 Rocketry

Black Arrow, officially capitalised BLACK ARROW, was a British satellite carrier rocket. Developed during the 1960s, it was used for four launches between 1969 and 1971. Its final flight was the first and only successful orbital launch to be conducted by the United Kingdom, and placed the Prospero satellite into low Earth orbit.

Black Arrow originated from studies by the Royal Aircraft Establishment for carrier rockets based on the Black Knight rocket, with the project being authorised in 1964. It was initially developed by Saunders-Roe, and later Westland Aircraft as the result of a merger.

Black Arrow was a three-stage rocket, fuelled by RP-1 paraffin (kerosene) and high test peroxide, a concentrated form of hydrogen peroxide (85% hydrogen peroxide + 15% water). It was retired after only four launches in favour of using American Scout rockets, which the Ministry of Defence calculated to be cheaper than maintaining the Black Arrow programme.

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🔗 Esterel – Synchronous programming language for complex, reactive systems

🔗 Computing 🔗 Computer science

Esterel is a synchronous programming language for the development of complex reactive systems. The imperative programming style of Esterel allows the simple expression of parallelism and preemption. As a consequence, it is well suited for control-dominated model designs.

The development of the language started in the early 1980s, and was mainly carried out by a team of Ecole des Mines de Paris and INRIA led by Gérard Berry in France. Current compilers take Esterel programs and generate C code or hardware (RTL) implementations (VHDL or Verilog).

The language is still under development, with several compilers out. The commercial version of Esterel is the development environment Esterel Studio. The company that commercialize it (Synfora) initiated a normalization process with the IEEE in April 2007 however the working group (P1778) dissolved March 2011. The Esterel v7 Reference Manual Version v7 30 – initial IEEE standardization proposal is publicly available.

🔗 Obsolete German Units of Measurement

🔗 Germany 🔗 Measurement

The obsolete units of measurement of German-speaking countries consist of a variety of units, with varying local standard definitions. Some of these units are still used in everyday speech and even in stores and on street markets as shorthand for similar amounts in the metric system. For example, some customers ask for one pound (ein Pfund) of something when they want 500 grams.

The metric system became compulsory on 1 January 1872, in Germany and on 1 January 1876, in Austria.

Some obsolete German units have names similar to units that were traditionally used in other countries, and that are still used in the United Kingdom (imperial units) and the United States (United States customary units).

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🔗 Grace Hopper

🔗 United States/U.S. Government 🔗 United States 🔗 Biography 🔗 Computing 🔗 Military history 🔗 Military history/North American military history 🔗 United States/Military history - U.S. military history 🔗 Military history/Military science, technology, and theory 🔗 New York City 🔗 Women scientists 🔗 Biography/science and academia 🔗 Women's History 🔗 Military history/Military biography 🔗 Biography/military biography 🔗 Software 🔗 Software/Computing 🔗 Military history/Maritime warfare 🔗 Pritzker Military Library

Grace Brewster Murray Hopper (née Murray December 9, 1906 – January 1, 1992) was an American computer scientist and United States Navy rear admiral. One of the first programmers of the Harvard Mark I computer, she was a pioneer of computer programming who invented one of the first linkers. She popularized the idea of machine-independent programming languages, which led to the development of COBOL, an early high-level programming language still in use today.

Prior to joining the Navy, Hopper earned a Ph.D. in mathematics from Yale University and was a professor of mathematics at Vassar College. Hopper attempted to enlist in the Navy during World War II but was rejected because she was 34 years old. She instead joined the Navy Reserves. Hopper began her computing career in 1944 when she worked on the Harvard Mark I team led by Howard H. Aiken. In 1949, she joined the Eckert–Mauchly Computer Corporation and was part of the team that developed the UNIVAC I computer. At Eckert–Mauchly she began developing the compiler. She believed that a programming language based on English was possible. Her compiler converted English terms into machine code understood by computers. By 1952, Hopper had finished her program linker (originally called a compiler), which was written for the A-0 System. During her wartime service, she co-authored three papers based on her work on the Harvard Mark 1.

In 1954, Eckert–Mauchly chose Hopper to lead their department for automatic programming, and she led the release of some of the first compiled languages like FLOW-MATIC. In 1959, she participated in the CODASYL consortium, which consulted Hopper to guide them in creating a machine-independent programming language. This led to the COBOL language, which was inspired by her idea of a language being based on English words. In 1966, she retired from the Naval Reserve, but in 1967 the Navy recalled her to active duty. She retired from the Navy in 1986 and found work as a consultant for the Digital Equipment Corporation, sharing her computing experiences.

The U.S. Navy Arleigh Burke-class guided-missile destroyer USS Hopper was named for her, as was the Cray XE6 "Hopper" supercomputer at NERSC. During her lifetime, Hopper was awarded 40 honorary degrees from universities across the world. A college at Yale University was renamed in her honor. In 1991, she received the National Medal of Technology. On November 22, 2016, she was posthumously awarded the Presidential Medal of Freedom by President Barack Obama.

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🔗 Silphium: Did Greek science die out because their elite discovered The Pill?

🔗 Food and drink 🔗 Plants 🔗 Alternative medicine 🔗 Women's Health

Silphium (also known as silphion, laserwort, or laser) was a plant that was used in classical antiquity as a seasoning, perfume, as an aphrodisiac, or as a medicine. It also was used as a contraceptive by ancient Greeks and Romans. It was the essential item of trade from the ancient North African city of Cyrene, and was so critical to the Cyrenian economy that most of their coins bore a picture of the plant. The valuable product was the plant's resin (laser, laserpicium, or lasarpicium).

Silphium was an important species in prehistory, as evidenced by the Egyptians and Knossos Minoans developing a specific glyph to represent the silphium plant. It was used widely by most ancient Mediterranean cultures; the Romans who mentioned the plant in poems or songs, considered it "worth its weight in denarii" (silver coins), or even gold. Legend said that it was a gift from the god Apollo.

The exact identity of silphium is unclear. It is commonly believed to be a now-extinct plant of the genus Ferula, perhaps a variety of "giant fennel". The still-extant plants Margotia gummifera and Ferula tingitana have been suggested as other possibilities. Another plant, asafoetida, was used as a cheaper substitute for silphium, and had similar enough qualities that Romans, including the geographer Strabo, used the same word to describe both.

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🔗 Microsoft Creative Writer (1993)

🔗 Computing 🔗 Computing/Software

Creative Writer is a word processor released by Microsoft Kids in 1993. Using this program, which is specifically targeted at children, it is possible to create documents such as letters, posters, flyers and stories complete with different fonts, Clip art, WordArt and effects. The interface and environment is especially targeted towards children and is set in Imaginopolis with the main helper being a character known as McZee. A sequel, Creative Writer 2, was released in 1996. Both are now discontinued, but can still be acquired from online stores and auction websites such as eBay.

The original Creative Writer was announced by Microsoft on 7 December 1993 and was released in 1994. It ran on both MS-DOS 3.2 and the Windows 3.1 operating system. A version was also released for the Apple Macintosh, compatible with computers running the classic Mac OS from the System 6 version up to Mac OS 9.

The program took place in the fictional place of Imaginopolis and had several levels of a building each with a different topic (e.g. one for plain writing, one for story templates, one for poster templates). The design of the program was very similar to that of its sister program Fine Artist. The program runs full screen and creates an all-inclusive environment. The interface was similar to a later product called Microsoft Bob.

Creative Writer featured many of the features found on Microsoft's Word for Windows product, including the WordArt feature used to create titles and headlines and the ability to add clip art. Creative Writer also used sounds heavily where each tool would make a different noise. Examples of this include a vacuum cleaner suction to delete and an explosion to denote deleting everything from a page.

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🔗 Beast of Gévaudan

🔗 France 🔗 Death 🔗 Dogs 🔗 Folklore

The Beast of Gévaudan (French: La Bête du Gévaudan, IPA: [la bɛt dy ʒevodɑ̃]; Occitan: La Bèstia de Gavaudan) is the historic name associated with a man-eating animal or animals that terrorized the former province of Gévaudan (consisting of the modern-day department of Lozère and part of Haute-Loire), in the Margeride Mountains of south-central France between 1764 and 1767.

The attacks, which covered an area spanning 90 by 80 kilometres (56 by 50 mi), were said to have been committed by one or more beasts of a tawny/russet colour with dark streaks/stripes and a dark stripe down its back, a tail "longer than a wolf's" ending in a tuft according to contemporary eyewitnesses. It was said to attack with formidable teeth and claws, and appeared to be the size of a calf or cow and seemed to fly or bound across fields towards its victims. These descriptions from the period could identify the beast as a young lion, a striped hyena, a large wolf, a large dog, or a wolfdog, though its identity is still the subject of debate.

The Kingdom of France used a considerable amount of wealth and manpower to hunt the animals responsible, including the resources of several nobles, soldiers, royal huntsmen, and civilians. The number of victims differs according to the source. A 1987 study estimated there had been 210 attacks, resulting in 113 deaths and 49 injuries; 98 of the victims killed were partly eaten. Other sources claim the animal or animals killed between 60 and 100 adults and children and injured more than 30. Victims were often killed by having their throats torn out. The beast was reported killed several times before the attacks finally stopped.

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🔗 MIPS R3000

🔗 Computing

The R3000 is a 32-bit RISC microprocessor chipset developed by MIPS Computer Systems that implemented the MIPS I instruction set architecture (ISA). Introduced in June 1988, it was the second MIPS implementation, succeeding the R2000 as the flagship MIPS microprocessor. It operated at 20, 25 and 33.33 MHz.

The MIPS 1 instruction set is small compared to those of the contemporary 80x86 and 680x0 architectures, encoding only more commonly used operations and supporting few addressing modes. Combined with its fixed instruction length and only three different types of instruction formats, this simplified instruction decoding and processing. It employed a 5-stage instruction pipeline, enabling execution at a rate approaching one instruction per cycle, unusual for its time.

This MIPS generation supports up to four co-processors. In addition to the CPU core, the R3000 microprocessor includes a Control Processor (CP), which contains a Translation Lookaside Buffer and a Memory Management Unit. The CP works as a coprocessor. Besides the CP, the R3000 can also support an external R3010 numeric coprocessor and two other external coprocessors.

The R3000 CPU does not include level 1 cache. Instead, its on-chip cache controller operates external data and instruction caches of up to 256 KB each. It can access both caches during the same clock cycle.

The R3000 found much success and was used by many companies in their workstations and servers. Users included:

  • Ardent Computer
  • Digital Equipment Corporation (DEC) for their DECstation workstations and multiprocessor DECsystem servers
  • Evans & Sutherland for their Vision (ESV) series workstations
  • MIPS Computer Systems for their MIPS RISC/os Unix workstations and servers.
  • NEC for their RISC EWS4800 workstations and UP4800 servers.
  • Prime Computer
  • Pyramid Technology
  • Seiko Epson
  • Silicon Graphics for their Professional IRIS, Personal IRIS and Indigo workstations, and the multiprocessor Power Series visualization systems
  • Sony for their PlayStation and PlayStation 2 (SCPH-10000 to SCPH-700XX - clocked at 37.5 MHz for use as an I/O CPU and at 33.8 MHz for compatibility with PlayStation games) video game consoles, and NEWS workstations, as well as the Bemani System 573 Analog arcade unit, which runs on the R3000A.
  • Tandem Computers for their NonStop Cyclone/R and CLX/R fault-tolerant servers
  • Whitechapel Workstations for their Hitech-20 workstation
  • New Horizons Probe

The R3000 was also used as an embedded microprocessor. When advances in technology rendered it obsolete for high-performance systems, it found continued use in lower-cost designs. Companies such as LSI Logic developed derivatives of the R3000 specifically for embedded systems.

The R3000 was a further development of the R2000 with minor improvements including larger TLB and a faster bus to the external caches. The R3000 die contained 115,000 transistors and measured about 75,000 square mils (48 mm2). MIPS was a fabless semiconductor company, so the R3000 was fabricated by MIPS partners including Integrated Device Technology (IDT), LSI Logic, NEC Corporation, Performance Semiconductor, and others. It was fabricated in a 1.2 μm complementary metal–oxide–semiconductor (CMOS) process with two levels of aluminium interconnect.

Derivatives of the R3000 for non-embedded applications include:

  • R3000A - A further development by MIPS introduced in 1989. It operated at clock frequencies up to 40 MHz.
  • PR3400 - Developed by Performance Semiconductor, introduced in May 1991, also at up to 40 MHz. It integrated the Performance Semiconductor PR3000A and PR3010A onto a single die.

Derivatives of the R3000 for embedded applications include:

  • PR31700 - A 75 MHz microcontroller from Philips Semiconductors. Fabricated in a 0.35 μm process, delivered in a 208-pin LQFP, it operated at 3.3 V and dissipated only 0.35 W.
  • RISController - A family of low-end microcontrollers from IDT. Models include the R3041, R3051, R3052, and R3081.
  • TX3900 - A microcontroller from Toshiba.
  • Mongoose-V - A radiation-hardened and expanded 10–15 MHz CPU for use on spacecraft, it is still in use today in applications such as NASA's New Horizons space probe.

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